The present invention relates to a telephone equipment of the cellular radiotelephone base station type.
The operator of a mobile telephone network distributes the base stations of the network across the territory to be covered, whereby the areas covered by the base stations define the cells. These base stations are linked to other mobile service infrastructures designed to route calls and link up with the wire-line networks.
Certain subscribers to the cellular network may have a wireless telephone station in their home or generally in a private place, similar to a private base station, directly connected to a wire-line telecommunication network. When the mobile station is communicating from the subscriber""s home, it accesses this private base station in preference to those of the cellular network. The call is therefore routed via the wire-line network and not via the cellular network. As a result of these arrangements, the subscriber can substitute his mobile handset for the wire-line terminal conventionally used at home.
An object of the present invention is to facilitate the use and installation of such private base stations.
Accordingly, the invention proposes a telephone equipment comprising a wire interface for connection to a wire-line telecommunication network and an air interface for communicating by radio with mobile stations in accordance with an operating mode of one type of cellular network, each mobile station operating in conjunction with a plug-in subscriber identity module containing parameters specific to the subscriber holding the mobile station and used to set up and/or operate radio calls. The equipment further comprises a data reader/recorder capable of receiving a subscriber identity module, reading therefrom at least one of the parameters specific to the subscriber and writing thereto other parameters dependent on the equipment, whereby telephone calls involving a mobile station located within range of the equipment and associated with an identity module that was previously inserted in the data reader/recorder can be set up via the wire-line network by means of the wire interface and the air interface.
The data reader/recorder enables the exchange, between the subscriber identity module and the private base station telephone equipment, of the parameters needed for the interaction of the base station and the mobile stations, i.e. on the one hand the parameters which allow the mobile station to identify the equipment as it is detected by radio and then take the required steps with the cellular network and, on the other hand, the parameters which enable the equipment to route incoming calls to the mobile station.
Use of this private station is not reserved for a single subscriber. A subscriber other than the one holding this equipment may register with this equipment by presenting his subscriber identity module to it. It is also conceivable for several subscriber modules to be registered simultaneously in order to be able to communicate via the equipment.
Another advantage is that the equipment may be issued to the user independently of the mobile station, which he may have acquired previously, in which case the reader/recorder merely has to read and re-programme the subscriber module presented to it.
Another aspect of the present invention relates to a telephone equipment of the private base station type comprising a wire interface for connection to a wire-line telecommunication network and an air interface for communicating by radio with mobile stations in accordance with an operating mode of one type of cellular network, wherein telephone communications involving a mobile station located within radio range of the equipment may be set up via the wire-line network using the wire interface and the air interface, and wherein the air interface is arranged to transmit a beacon signal in accordance with the operating mode of the type of cellular network, so that it can be detected by a mobile station located within radio range of the equipment and to cease transmitting the beacon signal during a call set up via the wire-line network and involving a mobile station. This equipment preferably incorporates the data reader/recorder defined above.
This equipment has the advantage of limiting the radio interference which it causes in the cellular network and/or other equipment of the same type. One simple solution is to arrange the air interface so that it occupies the physical channel of the beacon signal during said call involving the mobile station.
However, if several mobile stations are likely to communicate via the private base station (for example because their subscriber modules were successively submitted to the reader/recorder), the fact that one of them is making a call will cause the beacon signal to be interrupted and the equipment will no longer be detected by the other mobile station or stations. They will then locate on the cellular network so that they will still be capable of transmitting or receiving calls in spite of the fact that the line to which the equipment is connected is engaged.